Sputters on throttle

[xs650newb]

Hello,
I have been working hard getting my 1981 650 Special rideable.

I have cleaned set the cam chain tensioner, adjusted the valves, and cleaned the carbs (twice). The bike starts up and idles ok, with a very occasional misfire. With the bike on the centerstand I can rev it up and it sounds great, however, when I get on it to ride it sputter and dies when I put it in first gear and give it throttle.

Currently, I am running MikesXS Pods with open drag pipes. I am using a 45 pilot jet, 135 main jet, and the needle jet from Heiden's Tuning in the 3rd position from the top.

The battery is old and weak, however, the bike will rev perfectly fine on the center stand.

Any ideas?


Adam

 

[BigJimmyW13]

http://www.xs650.com/tech.php

 

[xs650newb]

What article did you have in mind? There are quite a few.

 

[BigJimmyW13]

Start in troubleshooting. That'd be a good one to start in and a good read for any FNG

 

[volcom8877]

Check the float/needle float hight the measurements are in the carb guide. I have and 81 and the same thing just happened to me. I fixed the hight and good as new I have stock pilot jet the small main is 135 the big main is 137.5

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[xs650newb]

Ok. I read through the guide. My fuel level in the float bowl was low in both carbs. I have a 1981 Special so I set the float height using a clear tube and making sure the gas level was no higher than the flange where the float bowl rests and no lower than 2mm below that point.

In addition, I synced the carbs which got rid of a backfiring problem I was having at idle.

Unfortunately, I cannot rev the bike without it dying. Here is what I have done

Cam chain - tightened according to spec
Valves - adjusted properly
Carb - cleaned, multiple times
Also, I am running a 137.5 main, 45 pilot, and the mixture screws are backed out 3 turns. All of this with open exhaust and mikes xs pods.

I went around the carb and sprayed starting fluid at various points, and the bike revved when I sprayed on the throttle shaft. I take this to mean I need new throttle shaft seals. Could this explain why the bike dies with throttle?

I already ordered them from Mikes and I read how they are installed from the carburetor guide.


Thanks,
Adam